The piston core

The orange barrel of the long core stowed on the starboard side of the ship. The 3 cranes are used to lift it over the side into the water.

2/25/10

We have been coring for a few days now, although the days start to blur together when instruments are being deployed nearly 24 hours a day. We were all fascinated to watch the jumbo piston core. The core barrel is over half the size of the Knorr. To quote the Knorr WHOI website:

“In 2006, the ship was refitted to support a new ‘long-coring’ system that can extract 60-meter (150-foot) plugs of ancient sediment from the seafloor. Weighing nearly 11 metric tons (25,000 pounds), the new piston-coring system is the longest in the U.S. research fleet (twice as long as existing systems).”

In order to deploy this massive piece of equipment, the core is lowered from its horizontal position on the deck and rotated to vertical underwater. It is then attached to the rear A-frame, and lowered below the boat. The rear deck of the boat has literally been sliced in half and reinforced to allow the core to hang on a pulley system under the deck.

Once brought back on board, the barrels inside the long core are removed and stored on 1.5m long segments.